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The paper aims to study the variation of electrical properties like electrical resistivity and current noise of a polymer thick film resistor, namely, PVC‐graphite thick film resistor, with parameters such as volume fraction, grain size, temperature and high voltage.

A model is proposed to explain the observed variations, which assumes that the texture of the polymer thick film resistor consists of insulator granules coated with conducting particles and also having cavities. The resistivity of these resistors is controlled mainly by the contact resistance between the conducting particles and the number of contacts each particle with its neighbors.

The variation of resistivity with temperature and high voltage is explained with the help of the model and it is attributed to the change in contact area and number of contacts. The current noise of these resistors is controlled mainly by the average relative resistance fluctuations between the conducting particles and the number of contacts each particle with its neighbors.

The variation of current noise with high voltage has also been explained with the help of this model and it is attributed to the change in number of conducting particles and conducting layers.

This study aims to examine how academic library directors conducted meetings in the change process and the factors influencing the approaches used.

Bolman and Deal's reframing change model provided the foundation for this research. An online survey was sent to 1,010 academic library directors in the USA. The response rate was 59 percent. The qualitative data were analyzed using content analysis. The collected quantitative and qualitative data were analyzed using descriptive (frequencies, percentages, means, standard deviations) and inferential statistics (binary and multinomial logistic regressions).

Most directors used multiple approaches to conduct meetings in the change process. The structural and human resource approaches were the most frequent single approaches. Regression analysis confirms that demographics, human capital, and library variables play significant roles in conducting meetings.

Data in this study were collected from directors in libraries of doctoral granting, master‐granting, and baccalaureate‐only colleges, and universities. Accordingly, the results of the study might not be generalized to college and university libraries outside this classification.

This paper provides a useful overview of the approaches used to conduct meetings in the change process and the factors influencing the approaches used.

Directors may use the results to reflect on different options of the strategies for conducting meetings in the change process and balance the weight of the factors' influences. The results may also help librarians better understand various approaches to conducting meetings in the change process.

As the textile industry increasingly engages with technical applications, interest in electronic textiles is growing. This paper reviews the research and development (R&D), and commercialization efforts in conducting polymers and electronic textile materials by using conducting polymers. A brief historical overview of conducting polymer development starts this paper. A review then documents the molecular orbitals and molecular structures of polymers, and lists some commonly used conducting polymer chemical structures, their band gap energies, corresponding dopants, and conductivity values. Then, there is a detailed discussion of the conducting mechanisms, with special attention paid to the energy band gap concept; the formation of polaron, soliton, and bipolaron. With regards to applications, the review presents conducting polymer applications, including antistatic packaging, microelectronics, rechargeable batteries, photovoltaic technology, LEDs, electrochromic devices, actuators, membranes, corrosion protection and biomedical applications, as well as applications of electric and electronic textiles (e-textiles) which include sensors, heaters, electromagnetic interference shielding, etc. Future trends in electrochromic and solar textiles conclude this paper.

The purpose of this paper is to describe a semi-analytical modeling technique to predict eddy currents in three-dimensional (3D) conducting structures with finite dimensions. Using the developed method, power losses and parasitic forces that result from eddy current distributions can be computed.

In conducting regions, the Fourier-based solutions are developed to include a spatially dependent conductivity in the expressions of electromagnetic quantities. To validate the method, it is applied to an electromagnetic configuration and the results are compared to finite element results.

The method shows good agreement with the finite element method for a large range of frequencies. The convergence of the presented model is analyzed.

Because of the Fourier series basis of the solution, the results depend on the considered number of harmonics. When conducting structures are small with respect to the spatial period, the number of harmonics has to be relatively large.

Because of the general form of the solutions, the technique can be applied to a wide range of electromagnetic configurations to predict, e.g. eddy current losses in magnets or wireless energy transfer systems. By adaptation of the conductivity function in conducting regions, eddy current distributions in structures containing holes or slit patterns can be obtained.

With the presented technique, eddy currents in conducting structures of finite dimensions can be modeled. The semi-analytical model is for a relatively low number of harmonics computationally faster than 3D finite element methods. The method has been validated and shown to be computationally accurate.

Teachers in the USA have been conducting lesson study for more than ten years since it was introduced from Japan in the late 1990s. Although interest in conducting lesson study in the USA is still strong and greater numbers of teachers have become involved in this professional learning, there are significant obstacles to conducting high quality and effective lesson study that enhances teachers’ content and pedagogical knowledge, as well as improving their instruction and student learning in classrooms. Because of the needs of improvement in lesson study in the USA, so it can be administered effectively and sustained, the purpose of this paper is to discuss the current status of lesson study in the USA, what high quality and effective lesson study is, and what ideas might be help to improve lesson study in the USA.

In this paper, issues that are common barriers to conducting effective lesson study, such as: US teachers’ misunderstanding or lack of understanding of lesson study; teachers’ insufficient knowledge of content, pedagogical content, curriculum knowledge; lack of support from administrators for lesson study; non‐systematic approach to implement lesson study; and having short‐sighted vision to conduct lesson study will be discussed. The discussions are based on the author's 12 years of experience working with teachers, schools, and school districts in the USA, interactions and information exchanges with other lesson study educators and researchers and professional development coordinators in schools and districts in the USA, and existing research documents in the USA. Through this discussion, the author attempts to provide suggestions for improving lesson study in the USA.

In order for lesson study to be successful, teachers need to think of lesson study as a way to improve their own learning as well as student learning. Spending more time studying mathematical content and curriculum, developing a strong pedagogical content knowledge with colleagues, and establishing a professional community of learning through lesson study will help it to be effective for improving classroom teaching and learning.

The paper provides some helpful suggestions for improving quality and effectiveness of lesson study in order to improve: classroom teaching – teacher's content, pedagogical content and curriculum knowledge; and student learning. The paper is particularly valuable for lesson study practitioners, and administrators and staff developers who are implementing lesson study in schools.

Fieldwork in emerging economies can be unpredictable and somewhat dangerous. The purpose of this article is to ascertain problematic issues that may arise when conducting qualitative research in emerging economies.

The author reflects on her fieldwork in Russia in 2014 and 2015. Specifically, the author provides a reflection on her investigation on how the Russian government influences Russian MNEs' ability to deal with domestic institutional complexity and gain external legitimacy.

The author has encountered a number of unforeseen difficulties: the ethical dilemma, sensitivity of the topic, translation challenges and unexpected group interviews. Through this reflection, he develops specific tactics on how to deal with these circumstances when conducting research outside a Western context. He also provides recommendations on how researchers in emerging economies can deal with ethical dichotomy created by the pressure to follow ethical guidelines. Finally, he identifies a list of opportunities that Russia presents as a research site.

The reflections on fieldwork discussed in this paper can prove to be useful for qualitative researchers interested in conducting qualitative research in Russia. In particular, it provides specific recommendations on how to navigate Russia as a research site.

This paper contributes to the literature on issues related to methodological issues related to conducting research in emerging economies, as well as under research contexts, such as Russia.

The purpose of this study is to explore the synthesis of novel conductive photo-resins to produce flexible conducting composites for use in additive manufacturing. By using direct ink writing (DIW) additive manufacturing, this study aims to explore the fabrication of multimaterial devices with conductive and insulating components. Using digital light processing (DLP) additive manufacturing, this study aims to fabricate detailed objects with higher resolution than material extrusion 3D printing systems.

In this paper, several photocurable conducting resins were prepared for DIW and DLP additive manufacturing. These resins were then cured using 405 nm near UV light to create intrinsically conductive polymer (ICP) composites. The electrochemical properties of these composites were analysed, and the effect of co-monomer choice and crosslinking density was determined. These results determined a suitable resin for subsequent additive manufacture using DIW and DLP. These 3D printing techniques were used to develop flexible conducting devices of submillimetre resolution that were fabricated with unmodified, commercially available 3D printers.

Cyclic voltammetry and volume conductivity analysis of the conducting resins determined the most conductive resin formula for 3D printing. Conductive devices were fabricated using the two 3D printing techniques. A multimaterial soft conducting device was fabricated using DIW, and each conducting component was insulated from its neighbours. DLP was used to fabricate a soft conducting device with good XY resolution with a minimum feature size of 0.2 mm. All devices were prepared in unmodified commercially available 3D printers.

These findings have value in the development of soft robotics, artificial muscles and wearable sensors. In addition, this work highlights techniques for DIW and DLP additive manufacturing.

Several original conducting resin formulae were developed for use in two 3D printing systems. The resulting 3D-printed composites are soft and flexible while maintaining their conductive properties. These findings are of value to both polymer chemists and to the field of additive manufacturing.

Although conducting polymers have various potential applications, lack of solubility is an impediment in their direct application to material surfaces. Synthesis of alkyl pyrrole monomers and subsequent polymerization into soluble conducting polymers are aimed as alternatives to conventional methods of application of conducting polymers on substrates. Alkyl chains are attached to a pyrrole ring to produce solubility in the resulting conducting polypyrroles, which allow direct application of conductive polymer emulsions to any desired surface. Friedel-Crafts acylation of the tosyl-protected pyrrole provides high yields of the 3-acylated product. The conductivity values of poly-3- and 3, 4-substituted pyrroles are generally less than the unmodified polypyrrole. Increasingly bulkier groups attached to the pyrrole means lower conductivity of the resultant polymer. As the carbon chain length attached to the 3-position of pyrrole increases, the solubility also increases. However, the magnitude of change in conductivity of films and pellets of soluble conducting polypyrroles over the alkyl range is not significant.

Passive conducting elements are the important parts of textronic systems. This paper aims to study a possibility of creating well-conducting and durable elements in textile materials by combining two technologies – physical vapour deposition (PVD) and laser patterning.

Thin conducting metallic layers on common fabrics do not provide satisfactory resistance to bending and stretching; therefore, selected textile composite materials have been proposed as a substrate. The conducting elements were produced in two stage process – deposition of thin metallic layer on textile composite and creating conducting elements by laser patterning. Laser ablation process was optimized using modelling in Comsol Multiphysics package. Properties of conducting structures were investigated experimentally and by modelling.

This paper confirms the correctness of the choice of the textile composite as a substrate for conducting elements. The results have shown that combining PVD deposition of thin metallic layer and controlled laser ablation allow creating passive elements such as resistors, inductive coils and heaters. Computer simulations conducted in the Comsol Multihysics environment enabled to determine the temperature distribution around the heaters and to describe the dynamics of its changes. The obtained results allow to shorten time of the optimization process of structures with different geometry and assumed temperature distribution.

The novelty of this research can be summarized as following: choosing of textile composites as substrates for conductive elements instead of textiles used so far in textronics; creating conductive structures on textile composites using combined technologies, PVD and laser patterning, for the first time; modelling of laser ablation process of thin metallic layer; and optimization of properties of conducting elements by computer modelling.

The aim of this paper is to present a method for calculating the electromagnetic fields, forces and current density distribution using Fourier series for a two-dimensional quasi steady state model consisting of a conducting uniform plate moving relative to an arbitrary current source with time harmonic excitation.

The presented solution is valid for an arbitrary source. A specific source is chosen consisting of a single coil made up of two-time harmonic current filaments. The solutions are derived and presented in a form that allows its expansion to include an arbitrary number of spatially shifted coils conducting arbitrary harmonic currents.

The analytical solution is compared to simulations produced using commercial finite element analysis software, ANSYS Maxwell2D and COMSOL, and is found to be in good agreement. The analytical solution provides a direct method to analyze the spatial harmonics in the system and can be computationally significantly faster especially at high relative speeds between the primary source and conducting plate.

The presented Fourier series solution is applied to simple 2-D model of a single coil with AC current excitation moving relative to a conducting plate. An analytical solution and analysis of this system has not been presented before, to the authors’ knowledge, using Fourier series or any other method.